Answer:
3
Step-by-step explanation:
17 * 3 = 51
51 * 3 = 153
153 * 3 = 459
etc.
Use proportions because we know that the triangles are similar.

Cross multiply.
20x=28×5
x=7
answer: 7
15/25 Divididing numerator and denominator by 5 we get:
3 / 5
84 and 6 i believe not sure tho
complementary adds to 90°